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Travel Diseases
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Japanese Encephalitis (JE) Geographic features conducive for the spread of JE include an abundance of rice fields, free standing water and heavy rains saturating the ground. JE is primarily transmitted by the bite of the Culex mosquito which has a preference for biting birds and swine. Infection is chiefly of domestic pigs and wading birds like herons and egrets which amplify the number of virus particles, thus enhancing transmission to non-infected mosquitoes. Humans are incidentally bitten and infected. About 1 in 200-300 infections results in symptomatic encephalitis (inflammation of the brain). Of these, about 1/3 of patients die, 1/3 have permanent brain damage and 1/3 recover. The brain injuries are severe with paralysis, seizures, permanent memory loss, and psychiatric problems. Nearly all adult inhabitants of certain risk areas show serologic evidence of previous infection and are immune, so that acute disease is seen mostly in children in those areas. Transmission is highest in rural areas and tends to be seasonal with epidemics. Year-round risk can occur depending on rain and irrigation practices. Suburban areas of major cities such as Bangkok, Beijing and Shanghai may have outbreaks. Urban outbreaks also may occur. The risk for travelers in temperate regions is almost exclusively during the rainy season.
All travelers to risk areas should take precautions to avoid mosquito bites. Those staying longer than one month or short term travelers having extensive outdoor exposure in rural areas, especially during high transmission seasons should consider vaccination. JE
vaccine JE-VAX® is an inactivated virus made from whole mouse brain. It is highly effective but has some disadvantages.
Urticaria (hives) and angioedema (swelling) of extremities, face and mouth can occur. A prior history of having allergic reactions may indicate a greater chance of have a serious allergic reaction Delayed reactions after vaccination may occur, for which reason, it is recommended that international travel not began until 10 days has passed since the last injection. The WHO recommends a booster every three years. IXIARO®
JE-VAX®
is no longer being produced, and limited
supplies remain. Therefore, the CDC currently recommends that
JE-VAX®
only be used for children aged 1-16 years of age. Malaria The Jesuit Cardinal Juan de Lugo is credited with propagating the use of bark from the cinchona tree of Peru for fever and chills. In the 1730s, James Lind a British navel surgeon, advocated the use of cinchona bark to prevent malaria on British ships, significantly reducing malaria in the British navy. Despite this, malaria continued to take a huge toll in military encounters and missionary endeavors. It is said that in the 19th century, the British and French had more losses from fever than bullets. Quinine the active ingredient in cinchona bark was disguised in wine and spirits because of its extreme bitterness and became known as the "Indian tonic water." As World War II approached, Japan took Java which contained most of the cinchona plantations. The Allies faced a serious quinine shortage and were forced to look to development of synthetic antimalarials. Some of those drugs continue to be used in malaria prevention or treatment today. New drugs have been developed since with newer ones in research studies. Only the female Anopheles species mosquitoes transmits malaria when taking a blood meal prior to laying eggs. Malaria protozoa are injected into the blood and take up residence in the liver to later emerge and infect red blood cells. Symptoms do not appear until the red blood cells are infected. Anopheles mosquitoes tend to prefer rural areas, though malaria may be contracted in cities, especially in Africa and India. There are four species of human malaria parasites. Two can remain asleep in the liver for months or years, reappearing long after exposure. Any person with unexplained fever and chills within a year of travel to a malarious area should be checked for malaria. Always tell your physician you were in a malarious area, if you are sick on returning home. Symptoms of malaria are often non-specific with high fever, teeth rattling chills and severe headache. Many travelers do not become ill until after returning home. Treatment can be as an out patient in those who are not seriously ill. There are two malaria species that are most commonly seen in returning travelers. Plasmodium falciparum infections usual present within 10 days of exposure and can rapidly become life threatening. Plasmodium vivax infections may not present until two weeks or even two months has passed since exposure. Malaria during pregnancy poses substantial risks to both mother and baby including prematurity and miscarriage. While traveling, if you or your local clinician believe you have malaria there may be no alternative but to submit to treatment where you are at, but ALWAYS take a blood smear home for later confirmation of the diagnosis. This is a simple smear of your blood on a glass slide. Do not have the slide stained or treated in any way. You should use personal protection with DEET or picaridin based insect repellants. Avoid mosquitoes from dusk to dawn. Bed netting should be used where good window screening is not part of residence. Many expatriates and locals will use bed netting regardless. Residence that are air conditioned afford significantly more mosquito protection that those not. Permethrin treatment of clothes and netting can be done for extra protection and is very helpful. Clothing can be purchased online that is pretreated with permethrin. Take your malaria medicine as prescribed by your physician. There is no vaccine for malaria. For a review of antimalarial medicines and how to take them, see Travel Medicines.
Meningococcal
Meningitis In Africa, it occurs in large epidemics in the sub-Sahara countries of the "meningitis belt." This is a narrow belt of geography which extends eastward across Africa from Mali to Ethiopia, and is uniquely high risk for epidemic meningitis. There are also epidemic prone countries South of the meningitis belt. Meningitis symptoms include high fever, lethargy, confusion, headache, nausea and vomiting. Convulsions may occur. This disease is far more than one of meningitis, and in fact, does not always cause meningitis. The meningococcal bacteria may spread in the blood stream to the skin and joints in which case, it is called meningococcal septicemia. Gangrenous, purplish black lesions on the digits and skin are seen. Rapid progression of gangrene of fingers, toes, arms, and legs may fail to be halted by antibiotics, necessitating amputation of multiple digits or extremities. This particular picture of gangrene is less common in Africa. In summary, a person may have meningococcal meningitis, meningococcal septicemia or both. The Neisseria meningitidis bacteria is highly contagious and spread by respiratory droplets and close contact, especially in households. In Africa and other developing countries, thousands of cases can occur prompting mass vaccination campaigns. There are five important groups (serotypes A, B, C, Y, and W135) of Neisseria meningitidis bacteria. All are vaccine preventable except for serotype B which occurs sporadically in developed countries including the US.
Meningitis Vaccines Menactra®, (also made by Sanofi Pasteur) became available in January 2005, which has better vaccination properties. Menactra® is licensed for persons 2-55 years of age. Many US travel medicine physicians prescribe Menactra® for adults of any age. Also, off-label vaccination with Menactra® may be considered for children < 2 years of age, given as 3 doses 4 weeks apart. Travel & Routine Immunizations 2009-2010, 18th ed, pg 149, Shoreland, Inc. Menactra® should be used preferentially over the older Menomune®. Menactra® is sometimes referred to as MCV which is an abbreviation for meningococcal conjugate vaccine. Menomune® is sometimes referred to as MPSV which is an abbreviation for meningococcal polysaccharide vaccine. Both vaccines are quadrivalent, which means they will protect against four groups or types (serotypes A, C, Y, and W135) of Neisseria meningitidis bacteria. Menactra® is recommended in these persons:
Menactra® should be considered in these persons:
Menactra® vaccine recommendations adapted from "Travel & Routine Immunizations" by Shoreland, pg. 141-4, Published 2008.
Menactra®
and pilgrimage to Mecca for Hajj or Umra.
Menactra®
boosters.
Menactra®
& Guillain-Barré Syndrome (GBS): Between October 2006 and January 2007 two additional cases occurred. Thus, there have been about 1.25 excess cases per million persons, ages 11-19 vaccinated.
GBS is rare and expected to occur in
non-vaccinated persons at nearly the same frequency. Experts have not
recommended discontinuing Menactra®
vaccinations.
Persons with a history of Guillain-Barré syndrome (GBS) might be at
increased risk for GBS after
Menactra®
vaccination. For more details
see this CDC site. Polio Polio attacks any age group but is most common in children which gave it the name "Infantile Paralysis." US epidemics resulted in hospitals over-flowing with victims and auditoriums filled with "iron lungs" holding one patient each. During epidemics, panic-stricken towns closed schools, theaters, swimming pools and cancelled events. Families would sometimes abandon their homes and flee to other parts of the country. Victims came to hospitals in waves and hospitals were in a state of emergency for weeks. Multiple family members became sick within days of each other. Families with sick children and arrivals from towns fleeing epidemics were shunned. Spread by close contact (fecal-oral) the polio virus infects the nervous system, destroying the anterior horn cells of the spinal cord leaving muscles un-empowered and wasting away. One or both legs shriveled to a fraction of normal size. If nerves to the muscles of respiration were affected, the victim would require an iron lung to assist breathing for months, years or indefinitely. Children and adults with braces or wheel chairs as a result of polio, has become an uncommon sight in the US, but not in many developing countries. The World Health Organization sponsors vaccination programs world wide. There have been no out breaks of paralytic polio in the Western Hemisphere since 1993, except in several very small groups. (In 2005, 30 or more cases of non-paralytic polio occurred in a Minnesota Amish community whose members predominantly were unvaccinated.)
Polio vaccines In 1961, the live attenuated vaccine was discovered by Sabin and administered to over 100 million Americans since the 1960's. Mass community campaigns called "Sabin Sundays" were organized to give this oral vaccine in purple colored sugar cubes. It is no longer used in the US because of it's rare potential to revert back to a wide virulent form, causing paralytic polio in susceptible close contacts. This type is still used widely in the world because of its easy administration and effectiveness.
Saudi Arabia entry requirements for polio vaccination were copied from "Travel & Routine Immunizations" by Shoreland, pg. 166-7, Published 2008.
Rabies Attacks may be non-provoked and involve multiple persons nearby. Travelers should avoid unnecessary contact with animals. Any bites should be washed with soap and water and dressed appropriately. A physician should be consulted immediately. Some countries have a high rate of human rabies cases which includes most developing countries in Asia, Africa and the Middle East. India has a particularly severe problem, with as many as 30,000 human deaths and 2 million people requiring postexposure vaccination yearly. Bangladesh and China also have serious problems. One expert remarked that China now has more dogs than people which compounds the problem. In 2007, China began initiating a "one dog, one family" policy and is expected to take serious action against Chinese rabies vaccine manufactures not meeting high quality production standards. Saliva contact from a rabid animal to mucous membranes and open wounds, bites no matter how trivial, a scratch and a scratch with a lick are grounds for vaccination. Awakening in a bed room or tent with a bat present is grounds for vaccination, even if there are no signs of a bite or scratch. Bat teeth are very small and bites may be undetectable. Spelunkers should receive pre-exposure vaccination. (One study in South Dakota, revealed that 4% of the bats tested were rabid.) Rabies symptoms appear as early as 10 to 14 days, but have been reported to appear as late as one year. In most cases, symptoms appear within two to three months. Thus, vaccination should be undertaken regardless of length of time since exposure. Vaccination after symptoms appear is never helpful. The virus multiples near the wound and reaches the brain via a nerve, not through the blood stream. After the virus reaches the brain, symptoms begin with intense itching in the wounded extremity, confusion, agitation, fearfulness and difficulty swallowing. Salivation may be profuse and paralysis sometimes occurs, giving the patient the appearance of having had a stroke. Once symptoms appear,
rabies is virtually always fatal. However, an usual case of survival has been reported in
a 15 year old girl who contracted rabies from a bat bite in Wisconsin. There are few diseases that equal rabies in suffering, both for patients and families. Because of this, patients with advanced symptoms are sometimes paralyzed with drugs and placed into a deep coma until death occurs.
Rabies vaccines
Vaccination can be done
before exposure (pre-exposure vaccination) or after exposure (post-exposure
vaccination) to rabies. Pre-exposure vaccination
The three dose rabies vaccination series (pre-exposure vaccination) is given over three weeks but does not eliminated the need for two boosters if exposure to rabies occurs. The first booster is given day 0 and a next on day 3. A tetanus booster should be received if not done in the past five years. These two boosters should not be delayed, however no person has ever contracted rabies while seeking vaccination within a few days of the exposure. Post-exposure vaccination
This must be accompanied by human rabies immunoglobulin (HRIG) injections within the first week of starting the series. If anatomically feasible, the full dose of HRIG should be thoroughly infiltrated in the area around and into the wounds. Any remaining volume of HRIG is given IM at a site distant from the vaccine. HRIG is difficult to find in developing countries and has been the reason for travelers leaving Africa to come home for treatment. This is a major reason vaccination is recommended before a prolonged trips to areas of high risk. Pregnancy and infancy are never contraindications to post-exposure vaccination. Rabies vaccination is virtually 100% effective if done properly. In the event of need for vaccination, travelers should not submit to the older brain tissue vaccine (Semple type vaccine). They should travel to a larger medical center where newer vaccines are administered or check local pharmacies. The following vaccines are widely used around the world:
A traveler started on any of the above vaccines in another country can have the series completed in the US with any licensed cell culture vaccine. Recommendations adapted from "Travel & Routine Immunizations" by Shoreland, pg. 170, Published 2008. If you start rabies vaccination in another country, request the following information from the clinic or private practitioner:
If a local health authority or physician is not available, contact the CDC:
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